1) Most users don't actually give a crap about "UX guidelines". I promise.
2) "UX guidelines" are, in my opinion, why our user interfaces continue to suck.
For example, IFileDialog maps to a Cocoa dialog on macOS, file picker on UWP, open dialog on Win32, document selector on Android and so on.
Yes, it takes some initial effort, but it only needs to be done once.
Do you need to design 5 designs that include 5 different buttons, 5 ways of navigating through the app, 5 different sets of icons, 5 different styles of animation, etc...
Hell even with a file picker, what happens when you use it on a platform that doesn't really have the concept of "files" like iOS or up to recently Android (at least in what is normally exposed to the user)
Roll in various versions of each OS and you are up to needing 10+ ways of doing most things. How are you supposed to create anything even remotely complicated?
It needs to be redone for each platform every few years as apis and visual styles change. Cross platform libraries are notoriously hard and usually end up in the uncanny valley (qt, swing etc).
Platform vendors of course any devs to buy into just one platform, they want and need the lock-in. Using web UI is a way to sidestep that.
Most applications are really crude in their design, and do not target large international hip demographics.
If you didn’t even take the effort to get your interface with your user (read: customer) right, how lazy did you get with the parts of the app I can’t see ?
A bad UI is a huge smell. In my experience there is a 1:1 relationship between the quality of the UI and the quality of the software as a whole.
